Ohh, that explains the really rich, deep colors they always used in the backgrounds. I loved the moody atmosphere that show managed to capture. Way ahead of its time, especially for a kids' cartoon.

I'm a dark-mode person on computers, and I'm also a visual artist. When I draw digitally I always prefer drawing light colors onto a dark background, and when I paint I always prefer painting lighter colors onto a black-primed canvas. I think I first tried that after seeing a behind-the-scenes about Batman's artists doing it that way, and realizing it made much more sense to my visual and artistic sensibility.